Re: [PATCH 12/15] [POWERPC] Add mpc52xx_restart(), mpc52xx_halt(), mpc52xx_power_off().

Add common MPC5200 helper routines: mpc52xx_restart(), mpc52xx_halt(),
mpc52xx_power_off().

This patch relies on Sascha Hauer's patch published in:
http://patchwork.ozlabs.org/linuxppc/patch?id=8910.

Signed-off-by: Marian Balakowicz <redacted>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---

 arch/powerpc/platforms/52xx/mpc52xx_common.c |   45 +++++++++++++++ 
++++++++++++
 include/asm-powerpc/mpc52xx.h                |    7 ++++
 2 files changed, 52 insertions(+)

diff --git a/arch/powerpc/platforms/52xx/mpc52xx_common.c b/arch/ 

powerpc/platforms/52xx/mpc52xx_common.c
index b1cd7b0..e7087d7 100644

--- a/arch/powerpc/platforms/52xx/mpc52xx_common.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_common.c

@@ -88,6 +88,14 @@ mpc52xx_find_ipb_freq(struct device_node *node)
 }
 EXPORT_SYMBOL(mpc52xx_find_ipb_freq);

+/*
+ * This variable is mapped in mpc52xx_setup_cpu() by a call to
+ * mpc52xx_find_and_map(), and used in mpc52xx_restart(). This is  

because
+ * mpc52xx_restart() can be called from interrupt context (e.g.,  
watchdog
+ * interrupt handler), and mpc52xx_find_and_map() (ioremap() to be  
exact)
+ * can't be called from interrupt context.
+ */
+volatile struct mpc52xx_gpt *mpc52xx_gpt0 = NULL;

 void __init
 mpc52xx_setup_cpu(void)

@@ -95,6 +103,9 @@ mpc52xx_setup_cpu(void)
 	struct mpc52xx_cdm  __iomem *cdm;
 	struct mpc52xx_xlb  __iomem *xlb;

+	/* mpc52xx_gpt0 is mapped here and used in mpc52xx_restart */
+	mpc52xx_gpt0 = mpc52xx_find_and_map("mpc5200-gpt");
+
 	/* Map zones */
 	cdm = mpc52xx_find_and_map("mpc5200-cdm");
 	xlb = mpc52xx_find_and_map("mpc5200-xlb");

@@ -138,3 +149,37 @@ mpc52xx_declare_of_platform_devices(void)
 			"Error while probing of_platform bus\n");
 }

+void
+mpc52xx_restart(char *cmd)
+{
+	local_irq_disable();
+
+	/* Turn on the watchdog and wait for it to expire. It effectively
+	  does a reset */
+	if (mpc52xx_gpt0) {
+		out_be32(&mpc52xx_gpt0->mode, 0x00000000);
+		out_be32(&mpc52xx_gpt0->count, 0x000000ff);
+		out_be32(&mpc52xx_gpt0->mode, 0x00009004);
+	} else
+		printk("mpc52xx_restart: Can't access gpt. "
+			"Restart impossible, system halted\n");
+
+	while (1);
+}
+
+void
+mpc52xx_halt(void)
+{
+	local_irq_disable();
+
+	while (1);
+}
+
+void
+mpc52xx_power_off(void)
+{
+	/* By default we don't have any way of shut down.
+	   If a specific board wants to, it can set the power down
+	   code to any hardware implementation dependent code */
+	mpc52xx_halt();
+}